Amer Bakhit Al-Maashani M, Hashim N. Upgrading Of Development Management Skills Among The Post-Primary Schools’ Principals At Dhofar Oman. perdanajournal [Internet]. 2019Aug.25 [cited 2026Apr.16];5(1):67-5. Available from: http://www.perdanajournal.com/index.php/perdanajournal/article/view/80